Peripheral neuropathy induced by drinking water contaminated with low-dose arsenic in Myanmar

Abstract

Background More than 140 million people drink arsenic-contaminated groundwater. It is unknown how much arsenic exposure is necessary to cause neurological impairment. Here, we evaluate the relationship between neurological impairments and the arsenic concentration in drinking water (ACDW). Participants and methods A cross-sectional study design was employed. We performed medical examinations of 1867 residents in seven villages in the Thabaung township in Myanmar. Medical examinations consisted of interviews regarding subjective neurological symptoms and objective neurological examinations of sensory disturbances. For subjective neurological symptoms, we ascertained the presence or absence of defects in smell, vision, taste, and hearing; the feeling of weakness; and chronic numbness or pain. For objective sensory disturbances, we examined defects in pain sensation, vibration sensation, and two-point discrimination. We analyzed the relationship between the subjective symptoms, objective sensory disturbances, and ACDW. Results Residents with ACDW ≥ 10 parts per billion (ppb) had experienced a “feeling of weakness” and “chronic numbness or pain” significantly more often than those with ACDW < 10 ppb. Residents with ACDW ≥ 50 ppb had three types of sensory disturbances significantly more often than those with ACDW < 50 ppb. In children, there was no significant association between symptoms or signs and ACDW. Conclusion Subjective symptoms, probably due to peripheral neuropathy, occurred at very low ACDW (around 10 ppb). Objective peripheral nerve disturbances of both small and large fibers occurred at low ACDW (> 50 ppb). These data suggest a threshold for the occurrence of peripheral neuropathy due to arsenic exposure, and indicate that the arsenic concentration in drinking water should be less than 10 ppb to ensure human health.

Quality and safety of municipal drinking water in Addis Ababa City, Ethiopia

“…This requires the isolation and enumeration of organisms that indicate the presence of fecal contamination. Yet, the quality and safety of drinking water was not determined by bacteriological parameters, but also physicochemical content of ion in the water maters for human health [24][25][26]. In certain circumstances, the same indicator organisms may also be used to assess the efficiency of drinking water treatment plants, which is an important element of quality control [27].…”

Arsenic Neurotoxicity in Humans

“…In low oxygen environments, such as deep well water or deep seawater, it is reduced to trivalent As (III). Sea water has an As concentration of approximately 2 ppb [7], whereas rain and river water have almost 0 ppb [6]. Despite these levels, the area most prescient for researchers remains As contamination of aquifers due to exposure risk.…”

“…Peripheral neuropathy due to chronic As exposure is caused by drinking water with As concentrations as low as 10–50 ppb [6]. The resulting impairment is observed predominantly in sensory fibers, and less so in motor fibers [5,47].…”

“…At least 140 million people in more than 50 countries are exposed to As-contaminated drinking water [3]. However, although a small number of acute As exposure patients have been studied in detail, relatively few studies have been performed on a detailed neuropathy of patients chronically exposed to As [4,5,6]. Although patients with chronic As exposure are numerous, their symptoms and clinical courses remain unclear.…”

Evaluation of the possible Immunomodulatory and Neuroprotective effects of γ-irradiated basil (Ocimum basilicum) against arsenic toxicity in rats

“…So, the increasing presence of an amount of arsenic in the environment present major risks, as exposure through inhalation, ingestion and dermal contact can cause various adverse effects on health (Vimercati et al, 2017). From these adverse health effects, the disorders of the nervous system (Mochizuki et al, 2019), immune system (Tutkun et al, 2019), digestive system (Chiocchetti, Vélez and Devesa, 2018), and respiratory system (Zhao et al, 2019). To treat these disorders has suggesting used complementary and alternative medicine (CAM) that may be as helpful.…”